收获期花生秧蔓切割锯盘设计与试验

为合理设计花生联合收获机切秧装置,在确定以旋转锯切为切秧方式的基础上,分析锯盘刀齿齿顶点和齿根点的运动特性,确定了锯盘的齿高、齿数、齿距等关键参数;通过对秧蔓切割时刀刃的受力分析发现合适的刀齿刃倾角可以减小工作时刀齿所受的阻力;建立了花生秧蔓的几何模型,并借助ANSYS/LS_DYNA进行关于盘厚、齿高、刃倾角的三因素三水平的切割仿真正交试验,试验以切割力为评价指标,确定了在盘厚5 mm、刃倾角20°、齿高17 mm为最优组合时,花生秧蔓的切割力最小为50 N;由自主设计的测力试验台所得试验值与仿真值的相对误差为3.24%,说明有限元仿真法对花生秧蔓切割力的测定是可行的。研究结果可为花生秧蔓切秧装置的设计和参数优化提供依据。

Design and experiment of cutting saw-disk for peanut vine during harvest period

In order to design the vine cutting device of peanut combine harvester reasonably,on the basis of determining the rotation sawing as the vine cutting mode,the motion characteristics of the apex and root points of the teeth of the saw disk cutter are analyzed,and the key parameters of the saw disk,such as tooth height,tooth number and tooth pitch are determined.Through the analysis of the force on the cutter edge of the seedling,it is found that the proper inclination of the cutter edge can reduce the resistance of the cutter edge.The geometric model of peanut vine was established and the orthogonal experiment of three factors and three levels of cutting simulation was carried out with the help of ANSYS_LS DYNA.The minimum cutting force of peanut vine was 50 N when the disc thickness was 5 mm,the blade angle was 20°and the tooth height was 17 mm.The relative error between the experimental value and the simulation value is 3.24%,which shows that the finite element simulation method is feasible to measure the cutting force of peanut vine.The results can provide the basis for the design and parameter optimization of peanut vine and vine cutting device.